Vehicle air-conditioning system

Abstract

A vehicle air-conditioning system limits electric power used by an electric motor for a compressor in a prescribed fashion that quickly removes fog from the windows when a defroster mode is selected. When the defroster mode is selected, the limit on the electric power used by the electric motor is lifted, and the number of revolutions of the compressor is set to a high level to raise the dehumidifying and cooling capability to quickly remove moisture from the windows.

What is claimed is:  
     
       1. A vehicle air-conditioning system comprising: 
       a compressor for compressing a refrigerant and discharging the compressed refrigerant;  
       an electric motor for driving said compressor; and  
       a heat exchanger for cooling air blown into a vehicle compartment by said refrigerant, electric power used by said electric motor being limited in a prescribed condition, wherein  
       the limit on the electric power used by the electric motor is lifted when a defogging blowing mode to blow said air to glass windows is selected.  
     
     
       2. The vehicle air-conditioning system according to  claim 1 , wherein 
       when said defogging blowing mode is selected, the number of revolutions of said compressor is increased to a target number of revolutions, and then held at said target number of revolutions for a prescribed period.  
     
     
       3. The vehicle air-conditioning system according to  claim 2 , wherein 
       when said defogging blowing mode is selected, the number of revolutions of said compressor is increased to said target number of revolutions at a maximum increasing speed for the number of revolutions.  
     
     
       4. The vehicle air-conditioning system according to  claim 2 , wherein 
       said prescribed period is determined based on at least one of a temperature of outside air, a temperature of said glass windows, and humidity in said vehicle compartment.  
     
     
       5. The vehicle air-conditioning system according to  claim 3 , wherein 
       said prescribed period is determined based on at least one of a temperature of outside air, a temperature of said glass windows, and humidity in said vehicle compartment.  
     
     
       6. The vehicle air-conditioning system according to  claim 2 , wherein 
       said target number of revolutions is determined based on at least one of a temperature of outside air, a temperature of said glass windows, and humidity in said compartment of the vehicle.  
     
     
       7. The vehicle air-conditioning system according to  claim 3 , wherein 
       said target number of revolutions is determined based on at least one of a temperature of outside air, a temperature of said glass windows, and humidity in said compartment of the vehicle.  
     
     
       8. The vehicle air-conditioning system according to  claim 4 , wherein 
       said target number of revolutions is determined based on at least one of a temperature of outside air, a temperature of said glass windows, and humidity in said compartment of the vehicle.  
     
     
       9. A vehicle air-conditioning system comprising: 
       a compressor for compressing a refrigerant and discharging the compressed refrigerant;  
       an electric motor for driving said compressor, said electric motor driven by a battery; and  
       a heat exchanger for cooling air using said refrigerant, said air blown into a vehicle compartment,  
       wherein the electric power used by said electric motor for said compressor is not limited when a defogging blowing mode is selected to blow air to vehicular glass windows.  
     
     
       10. The vehicle air-conditioning system according to  claim 9 , wherein 
       when said defogging blowing mode is selected, the number of revolutions of said compressor is increased to a target number of revolutions and held at said target number of revolutions for a prescribed period.  
     
     
       11. The vehicle air-conditioning system according to  claim 10 , wherein 
       when said defogging blowing mode is selected, the number of revolutions of said compressor is increased to said target number of revolutions at a maximum increasing speed for the number of revolutions.  
     
     
       12. The vehicle air-conditioning system according to  claim 11 , wherein 
       said target number of revolutions is set to a higher level while said engine is operated than while said engine is stopped.  
     
     
       13. The vehicle air-conditioning system according to  claim 10 , wherein 
       said target number of revolutions is higher at a high vehicle speed than at a low vehicle speed.  
     
     
       14. The vehicle air-conditioning system according to  claim 11 , wherein 
       said target number of revolutions is higher at a high vehicle speed than at a low vehicle speed.  
     
     
       15. The vehicle air-conditioning system according to  claim 10 , wherein 
       said prescribed period is changed based on whether or not said engine is operated.  
     
     
       16. The vehicle air-conditioning system according to  claim 14 , wherein 
       said prescribed period is changed based on whether or not said engine is operated.  
     
     
       17. The vehicle air-conditioning system according to  claim 13 , wherein 
       said prescribed period is changed based on the vehicle speed.  
     
     
       18. A vehicle air-conditioning system comprising: 
       a compressor for compressing a refrigerant and discharging the compressed refrigerant;  
       an electric motor for driving said compressor; and  
       a heat exchanger for cooling air blown into a compartment of a vehicle by said refrigerant,  
       wherein electric power used by said electric motor is limited in a prescribed condition, wherein the electric power used by said electric motor is greater when an instruction of defogging vehicle glass windows is issued in said prescribed condition than that when there is no such defogging instruction.